As telecommunications become increasingly important in everyday life, people are relying more and more on voice messaging systems. Voice messaging systems can be a large system adjunct to a PBX or switching system or a simple telephone answering machine. Voice messaging systems, both large and small, generally comprise a telephone line interface, an announcement or prompt mechanism and a recording/retrieval device, all of which are controlled by a processor. These systems answer the telephone after a predetermined number of rings. In more sophisticated systems, the voice messaging system answers when the called party is busy on another call. In either case, the system then prompts the calling party and records a message.
As common as voice messaging system are, however, many calling parties do not wait until the prompt is finished before beginning to speak. Many messages are lost or are incomplete because the calling party did not "wait for the tone" before speaking. The calling parties "barge in" as if the prompt were a human speaker that could be interrupted. Also, many callers are impatient over having to listen to a sometimes lengthy prompt before being able to record their messages. Therefore, a problem in the art is that calling parties often attempt to record a message without waiting for the end of the prompt.
Some voice messaging systems provide a feature whereby the calling party may interrupt the prompt by entering a code using dual-tone, multifrequency buttons (DTMF) on a push button phone. However, the caller must know the code for the particular voice messaging system, which is usually different for each system. As a result, few callers use DTMF barge in to interrupt a prompt message.
One system from a related field that provides prompt interrupt or "barge in" is described in U.S. Pat. No. 4,914,692, issued to Hartwell et al. on Apr. 3, 1990, and assigned to the assignee of this application. Hartwell describes a customer inquiry unit that initially responds to a telephone call received via the telephone network by transmitting an outgoing speech message to the customer. A portion of the speech of the message is reflected back to the inquiry system, due to the nature of the network. This is commonly called "echo". Hartwell discloses an echo canceler which adapts to the telephone network during an initial time period of the outgoing speech message and removes the echo of the outgoing speech message from the incoming signal. In case the customer starts to speak before the initial message is finished, the echo canceler transfers the enhanced incoming speech to a speech recognition subsystem for recognizing the content of the incoming speech.
The system of the Hartwell patent is described in connection specifically with complex speech recognition systems. Hartwell does not disclose how a typical simple answering machine or voice mail system may use echo cancellation to provide "barge in" for voice storage. Importantly, Hartwell does not disclose or discuss how to save the initial syllables of the incoming speech that would normally be lost due to the time-lag between detection of the incoming speech and activation of a recording device.
A problem in the art is that there is no voice messaging system with a voice activated prompt interrupt that will record an incoming message without losing the first part of the message.